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921.
Hungate BA Johnson DW Dijkstra P Hymus G Stiling P Megonigal JP Pagel AL Moan JL Day F Li J Hinkle CR Drake BG 《Ecology》2006,87(1):26-40
Experimentally increasing atmospheric CO2 often stimulates plant growth and ecosystem carbon (C) uptake. Biogeochemical theory predicts that these initial responses will immobilize nitrogen (N) in plant biomass and soil organic matter, causing N availability to plants to decline, and reducing the long-term CO2-stimulation of C storage in N limited ecosystems. While many experiments have examined changes in N cycling in response to elevated CO2, empirical tests of this theoretical prediction are scarce. During seven years of postfire recovery in a scrub oak ecosystem, elevated CO2 initially increased plant N accumulation and plant uptake of tracer 15N, peaking after four years of CO2 enrichment. Between years four and seven, these responses to CO2 declined. Elevated CO2 also increased N and tracer 15N accumulation in the O horizon, and reduced 15N recovery in underlying mineral soil. These responses are consistent with progressive N limitation: the initial CO2 stimulation of plant growth immobilized N in plant biomass and in the O horizon, progressively reducing N availability to plants. Litterfall production (one measure of aboveground primary productivity) increased initially in response to elevated CO2, but the CO2 stimulation declined during years five through seven, concurrent with the accumulation of N in the O horizon and the apparent restriction of plant N availability. Yet, at the level of aboveground plant biomass (estimated by allometry), progressive N limitation was less apparent, initially because of increased N acquisition from soil and later because of reduced N concentration in biomass as N availability declined. Over this seven-year period, elevated CO2 caused a redistribution of N within the ecosystem, from mineral soils, to plants, to surface organic matter. In N limited ecosystems, such changes in N cycling are likely to reduce the response of plant production to elevated CO2. 相似文献
922.
923.
Vyas Nimish B. Rattner Barnett A. Lockhart J. Michael Hulse Craig S. Rice Clifford P. Kuncir Frank Kritz Kevin 《Environmental science and pollution research international》2022,29(49):74024-74037
Environmental Science and Pollution Research - An important component of assessing the hazards of anticoagulant rodenticides to non-target wildlife is observations in exposed free-ranging... 相似文献
924.
Musah Mohammed Mensah Isaac Adjei Alfred Morrison Mahmood Haider Murshed Muntasir Omari-Sasu Akoto Yaw Boateng Frank Nyeadi Joseph Dery Coffie Cephas Paa Kwesi 《Environmental science and pollution research international》2022,29(21):31330-31347
Environmental Science and Pollution Research - One of the most commonly debated concerns regarding foreign direct investment inflows is the associated environmental adversities that accompany the... 相似文献